Tension device for overseaming sewing-machines.



R. e. WOODWARD. TENSION DEVIOE FOR OVERSEAMING SEWING MACHINES.

APPLICATION NILED JUNE 3, 1904.

Patented May 4, 1909.

AMI/Hey "barren stares earns I entree.

RUSSEL G. WOODWARD, OF WAUKEGAN, ILliINOIfi'ASSlGNO-RTO' UNION SFECIAL SEWING MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

TENSION DEVICE FOR OVERSEAMING SEWING-MACHINES.

No. season Specification of Letters Patent.

Patented May 4, 1909.

Application filed. June 3, 1904i Serial No. 211,005.

I 0 all whom it may concern: A 7

Be it known that I, RUssEL G. Woon- WARD, a citizen of the United States, residing at Vfaukegan, in the county of Lake, State of Illinois, have invented certain new and useful Improvements in Tension Devices for Overseaming Sewingddachines, of which the following is a description, reference being had to the accompanying drawing, and to the letters of reference marked thereon. J

The present invention relates to an improvement in overseaming sewing machines of the so-called three-thread type, in which a reciprocating thread-carrying needle is used, cooperating with two thread carrying loopers, one of which reoiprocates below the cloth plate and carries its thread through a loop of needle thread, and into position for another looper to carry itsthread, through the loop of the first looper thread, and up over the edge of the fabric into position to be engaged by the needle in its descent. In such an arrangement the thread of the looper, which reciprocates beneath the cloth plate, is practically laid vertically across the edge of the fabric. In the use of an overseaming machine of this character for finishing the edges and seaming ofgarments, it is desirable to provide a simple arrangement for varying the tension on the thread, which is laid againstthe edge, for the reason thatin sewing with the Wale of the goods less elasticity is required in the stitch than in sewing crosswise of the Wale. The third thread is used for giving more of covering to the edge of the fabric, and its tendency under tight tension is to draw the other threads close together, thus making a tight stitch. A more or less tight stitch is desirable in sewing lengthwise of the wale, as the goods are not so elastic in that direction, and of course, a tighter stitch gives a better covering. .More

elasticity is necessary, -however, in sewing across the Wale, as the goods are moreelastic in that direction, and to avoid the necessity of stopping the machine and regulating the tension when changing from one character of work to the other, I have rovided a simple device, readily worked y the operator, which can be set to certain desired limits of tight and loose tension. and by simple movement of the finger the tension can be changed to make either a tight or loose stitch.

matters hereinafter described and referred to 111 the appended claims.

The invention is illustrated in the accom- 'panying drawings, in which Figure 1 is a perspective view of so much of a sewing machine, embodying my invention,

as is necessary to a complete understanding thereof; Fig. 2 is a rear view, showing the po sitlon of the tenslon control when. set for supporting the parts of thetension controller,

with the trigger catch; Fig. 6 represents a detail of the tension disks, the spring and the sliding sleeve, against which one end of the spring bears. V v,

In the drawings, A represents a portion of the frameof the machine, B the needle lever; O the needle lever extension; D the needle bar; a the needle; 5 the looper, which lays its thread over the edge of the fabric, and whose thread is engaged by the needle in its descent; and c is the looper which engages the loop of needle thread and carries its own loop into position to allow a loop of thread of the looper b to be, passed therethrough. E is the throat plate. Upon the needle lever extension is secured the pull off at, thread being brought from the spool through an eye :chine standard, which carries the arm supporting the eyelet e, as well as another eyelet arm for the otherlooper thread. It is secured in, place by the tension posts G, H, of which the lower. one H is of ordinary construction, carrying the tension disksg, g, and

having the sleeve 7c, the spring-Z and the adjustingnut I. Secured upon the post H is a collar K, having a forked piece L, projecting therefrom, between the arms of which fork a pin or lugm depending from. the sleeve M is guided. Said collar K is adjustably mounted upon the post'H, and held in its adjusted position by means of a set screw K. This The invention, therefore, consists in the [sleeve is loose on the post, and has a yoke N,

with finger piece it and at the opposite end of the yoke is a ring 0, embracing the post and resting against the head of the sleeve 7c. Movement of the yoke longitudinally compresses or releases the spring Z, and, thereforetightens or loosens the pressure of the tension disks g, 9, upon the thread. The outer movement of the yoke is limited by the adjustable nut I.

In the normal position of the yoke, as shown in Fig. 2-, the disks 1, g, are under slight pressure from the spring Z, and a loose tension is provided for the thread 'i. If it is desired to get a tight stitch, the yoke is forced inward, and given a slight turn to force the in m into the notch 0, when the tension w1l remain taut until the operator swings the yoke upwardly, when the spring returns the parts to normal position.

It will be noted that the tension placed on the thread may be adjusted by adjusting the nut I, so that the outward throw of" the yoke will be greater, or by adjusting the collar K so that the yoke may be pushed in farther before engaging the locking notch, and thereby putting the spring under greater By this adjustment I am enabled to vary the degree of tension on the thread when under release and when under compression.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In an over-seaming sewing machine, and

in combination with a thread-carrying needle and complemental thread-carrying devices for laying threads on the top, bottom and across the edge of the material, tension device for the thread-carrying device laying its thread across the edge of the material, comprising tension disks, a spring controlling the same, means to compress or release said spring, and meanstor varying the degree of tension on the thread when under release, and when under compression; substantially as described.

2. In an overseaming sewing machine, and

in combination with, a thread-carrying nee dle, a thread carrying looper adapted to carry its thread through a loop of needle thread, and to one side the throat plate, and a second looper adapted to carry a loop of its thread through a loop of thread on the first looper up into position to be engaged by the needle in its next descent, and a tension device for the first mentioned looper thread, comprising tension disks, a spring controlling the same, and a sliding yoke adapted to compress or release the spring, and means for holding it in the position of compression of the tension spring; substantially as described.

3. A tension device for a sewing nmchine, comprising a tension post, disks thereon, a sliding yoke thereon, a spring between one end of said yoke and the disks, and means for holding the yoke in adjusted position against the pressure of the spring; substantially as described.

4. A tension device for a sewing nmchine, comprising a tension post, disks thereon, a. sliding yoke thereon, a. spring between. one end of said yoke and the disks, a collar on the post carrying a notched member, and a. pin or lug projecting from the yoke adapted to rest in said notch; substantially as described.

5. A tension device for sewing machines, comprising a. tension post, disks thereon, a spring controlling the disks, and a member sliding longitudinally on. the post andv acting against the spring to compress it In one movement, means on said post for holding said sliding member in said position and m ams for limiting the outward movement of said member; substantially as described.

6. A tension device for sewing machines, comprising a tension post, disks thereon, a collar thereon, having a guiding member and a notch therein, a yoke having a pin or lug, guided longitudinally by said. member, said pin or lug being adapted to engage said notch, said yoke also barring against a spring interposed between it and the disks; substantially as described.

7. A tension device for a. sewing machine, comprising a tension post, disks thereon, a sliding yoke thereon, a spring between one end of said yoke and the disks, an :uljustablccollar on the post carrying a, notched niember, and a pin or lug projecting from the yoke adapted to rest in said notch; s1|l' stan tially as described.

8. In combination with a spring pressed part, a member against which said part is pressed, a yoke, a support for said spring pressed part passing through th e arms of said yoke, a spring carried on said support and located between the arms of said yoke, an adjustable collar carried by said support For varying the tension of said spring.

In testimony whereof I allix my signature, in presence of two witnesses.

.RUSSEL G. VWJOIYW ill).

Witnesses:

C. MoNniL, A. B. CLo'rInnR.

(ill 

